Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
One can curb the forces of sense gratiﬁcation only by means of Krishnaconsciousness, or engaging all the senses in the transcendental loving service of the Lord. As enemies are curbed by superior force, the senses can similarly be curbed, not by any human endeavor, but only by keeping them engaged in the service of the Lord. One who has understood this – that only by Krishnaconsciousness is one really established in intelligence and that one should practice this art under the guidance of a bona ﬁde spiritual master – is called a sadhaka, or a suitable candidate for liberation.